Merocyanine dyes containing an aryloxy-, arylthio-, or arylselenoalkyl group attached to one of the nitrogen atoms thereof



iatenteci May 15,

UNITED STATES PATENT OFFICE MERQCYANIN'E :DYES CONTAINING AN ARXLOXY- ARYLTHIO-, on ARYLSE- LENOALKL .QROUP ATTACHED TO ONE .01 THE NITRQGEN ATOMS THEREOF Alfred W. Ariish, Vestal, N. assignor to General Aniline .&- Film Corporation, New York, N. Y., a corporation of Delaware No Drawing, Application April 1 2, 1950', Serial N0. 155,548

a Claims. (01. skit-524th 1 This invention relates to new dyes of the merocyanine type con aining a new group attached to the nitrogen atom of one of its nitrogenous hetcreases when the number of carbon atoms in the c alkyl group is increased.

.QknQWll that many nine es u va ydtb k a k' ta ylosyalkylh hzyl, t-ethoxyethyh n similar roup as substituents' on one or two of the cyanine niatoms have een t li e i the ho ra 1,9 r a sen i ng are Althqfig su dyes are satisfactory from the standpoint of soluh l ty and s t vit th y ar defic e f m standpoint of difiusiloility in multilayer film coati g Thus; the hydroXyalkylgroup is hydro- .Q and promotes water solubility, but does notpreve'nt diffusion. lnfasr'nucli as such groups do not prevent diffusion; it has been proposed by Wilmanns et al. in United States Patent 2,186,849 to introduce hydrophobic groups into the dye molecules. Unfortunately, the introduction of such substituents changes the dye "molecule to an extent which causes a modification of the sen sitizing characteristics.

It is recognized in the art thatthe greater the molecular weiglitof the substituent on a cyanine I dye, whether it be on the cya'nine nitrogen atom, polymethine chain or azole nucleus, the lower its solubility, discounting, of course, the presence of solubilizing groups. Hence, if (a sensitizing dye is deficient from the standpoint of difiusibility and satisfactory from the standpoint of solubility, a change in the size of the dye molecule to cure the defi eiency causes :a lessening of solubility. an bi t 9 t P esent v. ie yide an w class oi er ocyanine dyes containing ary dsval lill, l oal sy and .ary e noiallsyl groups attached to the nitrogen atom of Q 9 their m m tn ufi he e o ycli nu lei;

her obj ects andadvantages of this invention 1 become apparent by reference to the followpsfib lca idnl n which it p f rr d d ta ls and embodiments are-described, v I have discovered that by condensingaan N- aryloxyalkyl, N-arylthioalkyl, or N-arylselenowherein A is selected from the group consisting of O, S; and se-, m is a numeral ranging from 2 to is hume al rang-ing'fr'om l to 3; R is a-inember selected from the class consisting of an a y ro p 6- st m ylli opyl, i yl, amylg'isda'myl; h'e'ikyl', and the lili'e allyl; or faryl qi a as t em 1. naph h di s n l a 2; represents the atoms necessary to c'oinplete 5- Qr ,firm mbere heterocrl itr sepbiu of the type uses in cya'nine dye v t V olaub zqt iiazql benzos l'eil ole; ethy dioxyb'enzoxa'z'dle, indolenine; na hth'jox heaessat t'oj gbnimte a .5; or .v bei eq wheterocyclic nucleus, e. g, a barbituric acid, a t ber iiurmaq diarhnda ne.a qxazo ol one, -a..thi zol-9n a p ral l n hrdantoin. .a thin: h ifila t aa hionhenoneandthe like. Th ary group joined .to A is either a phenylor naphthyl group; ora phenyl group substituted by a methy JE etVhQXy, O a branched aliphaticchain, such as isopropyl; isobutyl, .d'i-isopropyl; .di-Tisobutyl, tert.-bu ty1, and the like; or cycloaliphatic, such as cyclohexyl, and the like.

The process of preparing the above merocyahine type dyes comprises heating, preferably under reflux, ,in the presence ,ofa tertiary base, an alcoholic solution of a quaternary cyclammonium salt characterized by the following general formula:

with a 5- or 6-membered ketoheterocyclic compound characterized by the following general formula:

wherein A, m, X and Y have the same values as above, 10- is a numeral ranging from 1 to 3, and Z represents an anionic acid radical, e. g., Cl, Br, I, C104, SO4CH3, 804021-15, SO3CsH4CI-I3, and the like.

The quaternary cyclammonium dye salts used in the preparation of the new dyes are described in my United States Patents 2,481,464 of September 6, 1949, and 2,496,842 of February 7, 1950.

The 5-membered ketoheterocyclic intermediates derived from a rhodanine, a thiazolone, a hydantoin, and the like are described in United States Patent 2,186,608.

As illustrative of ketoheterocyclic compounds represented by the foregoing formula, reference is made to:

:5- (5-acetanilido-A -pentadienylidene) -8-ethylrhodanine 5-(y-acetanilidopropenylidene) 2,4,6 triketohexahydropyrimidine 5-('y-acetanilidopropenylidene) -2-thio 4,6 diketohexahydropyrimidine, and the like.

The merocyanine type dyes may also be prepared by condensing a quaternary cyclammonium dye salt containing in place of the reactive methyl group in aor v-position to the nitrogen atom thereof a reactive anilinovinyl, acylanilidovinyl,

e. g., acetanilidovinyl, etc., alkylthio, e. g., methyl- .thio, ethylthio, arylthio, e. g., phenylthio, etc.,

alkylor arylthiovinyl, e. g., ethylthiovinyl, phenylthiovinyl, and the like or halogenovinyl group, e. g., 2-chlorovinyl, 2-bromovinyl, etc., with an N-substituted 5- or 6-membered ketomethylene heterocyclic compound of the type commonly 4 employed in merocyanine dyes and characterized by the following general formula:

wherein R and Y have the same values as above.

The quaternary cyclammonium dye salts containing anilinovinyl, acylanilidovinyl, etc., reactive groups are described in m United States Patent 2,496,842.

As typical examples of the N-substituted 5- or 6-membered ketomethylene compounds, the following may be mentioned:

3-ethylrhodanine 3-allylrhodanine 3-phenylrhodanine 3-benzylrhodanine 3-methyl-4-keto-2-thiotetrahydroxazole 3-phenyl-4-keto-2-thiotetrahydroselenazole 3-propyl-4-keto-2-selenotetrahydrothiazole 1-phenyl-3-methyl-5-pyrazo1one 1-methyl-5-pyrazolone 1,3-dimethyl-5-pyrazolone 1,3-diphenyl-5-pyrazolone 3-phenyl-2,4-thiazoledione 2-diphenylamino-3-ethyl-4(5) -thiaz0lone 3-ethyl-2-thio-2,4(3,5) -oxazoledione 3-ethyl-1-phenyl-2-thiohydantoin 2,4,6-triketohexahydropyrimidin 2-thio-4,6-diketohexahydropyrimidine, and the like.

The following alcohols may be employed as solvent-diluent in the condensation reaction: methanol, ethanol, propanol, butanol, benzylalcohol, furfuryl alcohol, and the like. Triethylamine, tributylamine and the like are representative of the tertiary bases which may be employed as the catalyst.

The following examples describe in detail the 'methods for accomplishing the above objects,

but it is to be understood that they are inserted merely for the purpose of illustration and are not to be construed as limitative.

Emample I A mixture of 4.73 grams of 2-methylmercaptobenzothiazole fi-phenoxyethyl p-toluenesulfonate, 1.61 grams of 3-ethylrhodanine, and 0.35 gram of triethylamine dissolved in 30 cc. of absolute ethanol was refluxed on a steam bath for about 1 hour, during which time the dye separated from the hot alcohol. The mixture was filtered while hot and the filter residue boiled out twice with 50 cc. portions of methanol. The dye was purified by dissolving in dioxane and precipitating with alcohol.

Example II \T e g ams ae at wmthylh ea thiw e phenoxyethyl p-toluenesulfonate and 3-ally1:: acetanilidomethylenerhodanine were dissolved in 50 cc. of hot isopropanol and 0.5 cc. of triethylamine added. The mixture was refluxed for 30 minutes and the crystals of dye which formed on cooling the reaction mixture were filtered. The dye was purified by dissolving in dioxane and precipitating with 95% ethyl alcohol. It has a melting point of 234 C.

Eicample III CHaO --S6 Equimolecular proportions of 5,-i('y-acetanilidopropenylidene)-3-ethy1rhodanine and 2-methy1- G-methoxy-benzoselenazole fl-phenoxyethyl ptoluenesulfonate were condensed as in Example II.

Example of 5 acetanilidomethylene 3 ethyl 2 thio J 2,4 (3,5) -oxazolidone.

Exam le V 6 n h danto n i em l e as the ke q ylene o o nd o in hebr edu s of Example he dye of the above formula is bb ialn When 4 (y acetanilidopropenylidene) 3 methyl-*1-phenyl-5-pyrazolone is employed as the ketomethylene compound following the procedure of Example II, a dye having the above formula is obtained.

While thepresent invention has been described considerable detail to a new class of merocyanine type dyes, it is to be understood that the rhodacyanine and rhodacarb'ocyanine dyes can be very readily prepared from the dyes prepared in accordance with the foregoing examples. For example, the merocyanine type dyes which contain a rhodanine, hydantoin, oxazoledione nucleus, as illustrated in Examples I to V, may be further treated with a quarternizi ng compound, such as dimethyl sulfate or methyl iodide. The quaternized compound is then condensed under reflux with a quaternary cyclammonium heterocyclic base or dye salt usual in cyanine dyes, such as 3-methy1-2 methylbzenzothiazole ethicdide having a reactive methyl group in a-position to the nitrogen atom in the presence of a condensing agent, such as pyridine, quinoline, and the like. In the first reaction (alkylation), the merocyanine dye is modified to the extent that the nitrogen atom in the 3-position of the rhodanine, hydantoin, or oxazoledione ring is quaternized and the sulfur atom in the 2 'position is converted to ca thi'oether group. In the second reaction (condensation), the alkylated merecyanine dye is condensed with :a quaternary cyclammonium base or salt whereby rhod'a cyanine and rhodacarbocyanine dyes are obam d-t.

The following examples are illustrative of the preparation of such dyestuffs:

Five-tenths gram or the-dye prepared in Example II was mixed with 10 cc. of 'dimethyl suliatefand heatedat C. for 10 minutes. T e

When 5-('y acetahilidoiiiopenylidene) -3-ethy1- "75 mixture-was "chilled in "ice water ane "a "large excess of pyridine added, followed by 0.3 gram of Z-methylbenzothiazole ethiodide. The, new mixture was refluxed for 30 minutes and then cooled. Upon adding cc. of water and allowin to stand, a dye precipitated. The dye crystals which separated were filtered off and boiled out with a dioxane methanol mixture. The dye was recrystallized from methanol.

ExampZe VIII 1 $311 lHa) a Instead of employing 2 -methylbenzothiazole ethiodide as in Example VII, there isemployed an equivalent amount of Z-methylbenzoxazole vphenoxypropyl p-toluenesulfonate.

Instead of employing 2 -methylbenzothiazole ethiodide as in Example VII, there is employed 3-phenylrhodanine.

This application is a continuation-inpart of my application Serial No. 638,496, filed on December 29, 1945, now United States Patent 2,504,- 615 of April 18, 1950.

I claim:

1. A merocyanine dye having the general formula:

wherein A is selected from the group consisting of O, S, and Se, m is a numeral ranging from 2 to 3, n is a numeral ranging from 1 to 3, R is selected from the group consisting of alkyl, allyl, and aryl groups, X represents the atoms necessary to complete a heterocyclic nitrogenous nucleus of the type usual in cyanine dyes, and Y represents the atoms necessaryrto complete a member selected from the class consistirigoffiand 6-membered ketoheterocyclic ring system.

mula:

-' 3. Y A merocyanine 2. A merocyanine dye of the following fordye of the following for- 4. A merocyanine dye of the following formula:

CH O- 5. A merocyanine dye of the following formula (g aHs 6. A merocyanine dye of the following formula:

ALFRED W. ANISH.

No references cited. 

1. A MEROCYANINE DYE HAVING THE GENERAL FORMULA: 